From faad5de0b10484d3dc2ed2a803b2b82f6b1b81ee Mon Sep 17 00:00:00 2001 From: Anatolij Gustschin Date: Fri, 11 Apr 2014 08:57:14 +0200 Subject: [PATCH] watchdog: imx2_wdt: convert to watchdog core api Convert the imx2_wdt driver to the new watchdog core api. Signed-off-by: Anatolij Gustschin Reviewed-by: Guenter Roeck Cc: Wolfram Sang Signed-off-by: Wim Van Sebroeck --- drivers/watchdog/Kconfig | 1 + drivers/watchdog/imx2_wdt.c | 292 +++++++++++++++--------------------- 2 files changed, 123 insertions(+), 170 deletions(-) diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 65ef91e3e497..9360c5525fa9 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -379,6 +379,7 @@ config IMX2_WDT tristate "IMX2+ Watchdog" depends on ARCH_MXC select REGMAP_MMIO + select WATCHDOG_CORE help This is the driver for the hardware watchdog on the Freescale IMX2 and later processors. diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c index 76fa724930ca..9d4874f09948 100644 --- a/drivers/watchdog/imx2_wdt.c +++ b/drivers/watchdog/imx2_wdt.c @@ -22,18 +22,15 @@ */ #include -#include #include #include #include #include -#include #include #include #include #include #include -#include #include #define DRIVER_NAME "imx2-wdt" @@ -56,19 +53,12 @@ #define WDOG_SEC_TO_COUNT(s) ((s * 2 - 1) << 8) -#define IMX2_WDT_STATUS_OPEN 0 -#define IMX2_WDT_STATUS_STARTED 1 -#define IMX2_WDT_EXPECT_CLOSE 2 - -static struct { +struct imx2_wdt_device { struct clk *clk; struct regmap *regmap; - unsigned timeout; - unsigned long status; struct timer_list timer; /* Pings the watchdog when closed */ -} imx2_wdt; - -static struct miscdevice imx2_wdt_miscdev; + struct watchdog_device wdog; +}; static bool nowayout = WATCHDOG_NOWAYOUT; module_param(nowayout, bool, 0); @@ -86,11 +76,12 @@ static const struct watchdog_info imx2_wdt_info = { .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, }; -static inline void imx2_wdt_setup(void) +static inline void imx2_wdt_setup(struct watchdog_device *wdog) { + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); u32 val; - regmap_read(imx2_wdt.regmap, IMX2_WDT_WCR, &val); + regmap_read(wdev->regmap, IMX2_WDT_WCR, &val); /* Suspend timer in low power mode, write once-only */ val |= IMX2_WDT_WCR_WDZST; @@ -101,157 +92,93 @@ static inline void imx2_wdt_setup(void) /* Keep Watchdog Disabled */ val &= ~IMX2_WDT_WCR_WDE; /* Set the watchdog's Time-Out value */ - val |= WDOG_SEC_TO_COUNT(imx2_wdt.timeout); + val |= WDOG_SEC_TO_COUNT(wdog->timeout); - regmap_write(imx2_wdt.regmap, IMX2_WDT_WCR, val); + regmap_write(wdev->regmap, IMX2_WDT_WCR, val); /* enable the watchdog */ val |= IMX2_WDT_WCR_WDE; - regmap_write(imx2_wdt.regmap, IMX2_WDT_WCR, val); + regmap_write(wdev->regmap, IMX2_WDT_WCR, val); } -static inline void imx2_wdt_ping(void) +static inline bool imx2_wdt_is_running(struct imx2_wdt_device *wdev) { - regmap_write(imx2_wdt.regmap, IMX2_WDT_WSR, IMX2_WDT_SEQ1); - regmap_write(imx2_wdt.regmap, IMX2_WDT_WSR, IMX2_WDT_SEQ2); -} + u32 val; -static void imx2_wdt_timer_ping(unsigned long arg) -{ - /* ping it every imx2_wdt.timeout / 2 seconds to prevent reboot */ - imx2_wdt_ping(); - mod_timer(&imx2_wdt.timer, jiffies + imx2_wdt.timeout * HZ / 2); + regmap_read(wdev->regmap, IMX2_WDT_WCR, &val); + + return val & IMX2_WDT_WCR_WDE; } -static void imx2_wdt_start(void) +static int imx2_wdt_ping(struct watchdog_device *wdog) { - if (!test_and_set_bit(IMX2_WDT_STATUS_STARTED, &imx2_wdt.status)) { - /* at our first start we enable clock and do initialisations */ - clk_prepare_enable(imx2_wdt.clk); - - imx2_wdt_setup(); - } else /* delete the timer that pings the watchdog after close */ - del_timer_sync(&imx2_wdt.timer); + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); - /* Watchdog is enabled - time to reload the timeout value */ - imx2_wdt_ping(); + regmap_write(wdev->regmap, IMX2_WDT_WSR, IMX2_WDT_SEQ1); + regmap_write(wdev->regmap, IMX2_WDT_WSR, IMX2_WDT_SEQ2); + return 0; } -static void imx2_wdt_stop(void) +static void imx2_wdt_timer_ping(unsigned long arg) { - /* we don't need a clk_disable, it cannot be disabled once started. - * We use a timer to ping the watchdog while /dev/watchdog is closed */ - imx2_wdt_timer_ping(0); + struct watchdog_device *wdog = (struct watchdog_device *)arg; + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); + + /* ping it every wdog->timeout / 2 seconds to prevent reboot */ + imx2_wdt_ping(wdog); + mod_timer(&wdev->timer, jiffies + wdog->timeout * HZ / 2); } -static void imx2_wdt_set_timeout(int new_timeout) +static int imx2_wdt_set_timeout(struct watchdog_device *wdog, + unsigned int new_timeout) { - regmap_update_bits(imx2_wdt.regmap, IMX2_WDT_WCR, IMX2_WDT_WCR_WT, + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); + + regmap_update_bits(wdev->regmap, IMX2_WDT_WCR, IMX2_WDT_WCR_WT, WDOG_SEC_TO_COUNT(new_timeout)); + return 0; } -static int imx2_wdt_open(struct inode *inode, struct file *file) +static int imx2_wdt_start(struct watchdog_device *wdog) { - if (test_and_set_bit(IMX2_WDT_STATUS_OPEN, &imx2_wdt.status)) - return -EBUSY; + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); - imx2_wdt_start(); - return nonseekable_open(inode, file); + if (imx2_wdt_is_running(wdev)) { + /* delete the timer that pings the watchdog after close */ + del_timer_sync(&wdev->timer); + imx2_wdt_set_timeout(wdog, wdog->timeout); + } else + imx2_wdt_setup(wdog); + + return imx2_wdt_ping(wdog); } -static int imx2_wdt_close(struct inode *inode, struct file *file) +static int imx2_wdt_stop(struct watchdog_device *wdog) { - if (test_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status) && !nowayout) - imx2_wdt_stop(); - else { - dev_crit(imx2_wdt_miscdev.parent, - "Unexpected close: Expect reboot!\n"); - imx2_wdt_ping(); - } - - clear_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status); - clear_bit(IMX2_WDT_STATUS_OPEN, &imx2_wdt.status); + /* + * We don't need a clk_disable, it cannot be disabled once started. + * We use a timer to ping the watchdog while /dev/watchdog is closed + */ + imx2_wdt_timer_ping((unsigned long)wdog); return 0; } -static long imx2_wdt_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) +static inline void imx2_wdt_ping_if_active(struct watchdog_device *wdog) { - void __user *argp = (void __user *)arg; - int __user *p = argp; - int new_value; - u32 val; + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); - switch (cmd) { - case WDIOC_GETSUPPORT: - return copy_to_user(argp, &imx2_wdt_info, - sizeof(struct watchdog_info)) ? -EFAULT : 0; - - case WDIOC_GETSTATUS: - return put_user(0, p); - - case WDIOC_GETBOOTSTATUS: - regmap_read(imx2_wdt.regmap, IMX2_WDT_WRSR, &val); - new_value = val & IMX2_WDT_WRSR_TOUT ? WDIOF_CARDRESET : 0; - return put_user(new_value, p); - - case WDIOC_KEEPALIVE: - imx2_wdt_ping(); - return 0; - - case WDIOC_SETTIMEOUT: - if (get_user(new_value, p)) - return -EFAULT; - if ((new_value < 1) || (new_value > IMX2_WDT_MAX_TIME)) - return -EINVAL; - imx2_wdt_set_timeout(new_value); - imx2_wdt.timeout = new_value; - imx2_wdt_ping(); - - /* Fallthrough to return current value */ - case WDIOC_GETTIMEOUT: - return put_user(imx2_wdt.timeout, p); - - default: - return -ENOTTY; + if (imx2_wdt_is_running(wdev)) { + imx2_wdt_set_timeout(wdog, wdog->timeout); + imx2_wdt_timer_ping((unsigned long)wdog); } } -static ssize_t imx2_wdt_write(struct file *file, const char __user *data, - size_t len, loff_t *ppos) -{ - size_t i; - char c; - - if (len == 0) /* Can we see this even ? */ - return 0; - - clear_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status); - /* scan to see whether or not we got the magic character */ - for (i = 0; i != len; i++) { - if (get_user(c, data + i)) - return -EFAULT; - if (c == 'V') - set_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status); - } - - imx2_wdt_ping(); - return len; -} - -static const struct file_operations imx2_wdt_fops = { +static struct watchdog_ops imx2_wdt_ops = { .owner = THIS_MODULE, - .llseek = no_llseek, - .unlocked_ioctl = imx2_wdt_ioctl, - .open = imx2_wdt_open, - .release = imx2_wdt_close, - .write = imx2_wdt_write, -}; - -static struct miscdevice imx2_wdt_miscdev = { - .minor = WATCHDOG_MINOR, - .name = "watchdog", - .fops = &imx2_wdt_fops, + .start = imx2_wdt_start, + .stop = imx2_wdt_stop, + .ping = imx2_wdt_ping, + .set_timeout = imx2_wdt_set_timeout, }; static struct regmap_config imx2_wdt_regmap_config = { @@ -263,76 +190,101 @@ static struct regmap_config imx2_wdt_regmap_config = { static int __init imx2_wdt_probe(struct platform_device *pdev) { + struct imx2_wdt_device *wdev; + struct watchdog_device *wdog; struct resource *res; void __iomem *base; int ret; + u32 val; + + wdev = devm_kzalloc(&pdev->dev, sizeof(*wdev), GFP_KERNEL); + if (!wdev) + return -ENOMEM; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(base)) return PTR_ERR(base); - imx2_wdt.regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base, - &imx2_wdt_regmap_config); - if (IS_ERR(imx2_wdt.regmap)) { + wdev->regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base, + &imx2_wdt_regmap_config); + if (IS_ERR(wdev->regmap)) { dev_err(&pdev->dev, "regmap init failed\n"); - return PTR_ERR(imx2_wdt.regmap); + return PTR_ERR(wdev->regmap); } - imx2_wdt.clk = devm_clk_get(&pdev->dev, NULL); - if (IS_ERR(imx2_wdt.clk)) { + wdev->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(wdev->clk)) { dev_err(&pdev->dev, "can't get Watchdog clock\n"); - return PTR_ERR(imx2_wdt.clk); + return PTR_ERR(wdev->clk); } - imx2_wdt.timeout = clamp_t(unsigned, timeout, 1, IMX2_WDT_MAX_TIME); - if (imx2_wdt.timeout != timeout) - dev_warn(&pdev->dev, "Initial timeout out of range! " - "Clamped from %u to %u\n", timeout, imx2_wdt.timeout); + wdog = &wdev->wdog; + wdog->info = &imx2_wdt_info; + wdog->ops = &imx2_wdt_ops; + wdog->min_timeout = 1; + wdog->max_timeout = IMX2_WDT_MAX_TIME; - setup_timer(&imx2_wdt.timer, imx2_wdt_timer_ping, 0); + clk_prepare_enable(wdev->clk); - imx2_wdt_miscdev.parent = &pdev->dev; - ret = misc_register(&imx2_wdt_miscdev); - if (ret) - goto fail; + regmap_read(wdev->regmap, IMX2_WDT_WRSR, &val); + wdog->bootstatus = val & IMX2_WDT_WRSR_TOUT ? WDIOF_CARDRESET : 0; - dev_info(&pdev->dev, - "IMX2+ Watchdog Timer enabled. timeout=%ds (nowayout=%d)\n", - imx2_wdt.timeout, nowayout); - return 0; + wdog->timeout = clamp_t(unsigned, timeout, 1, IMX2_WDT_MAX_TIME); + if (wdog->timeout != timeout) + dev_warn(&pdev->dev, "Initial timeout out of range! Clamped from %u to %u\n", + timeout, wdog->timeout); + + platform_set_drvdata(pdev, wdog); + watchdog_set_drvdata(wdog, wdev); + watchdog_set_nowayout(wdog, nowayout); + watchdog_init_timeout(wdog, timeout, &pdev->dev); + + setup_timer(&wdev->timer, imx2_wdt_timer_ping, (unsigned long)wdog); -fail: - imx2_wdt_miscdev.parent = NULL; - return ret; + imx2_wdt_ping_if_active(wdog); + + ret = watchdog_register_device(wdog); + if (ret) { + dev_err(&pdev->dev, "cannot register watchdog device\n"); + return ret; + } + + dev_info(&pdev->dev, "timeout %d sec (nowayout=%d)\n", + wdog->timeout, nowayout); + + return 0; } static int __exit imx2_wdt_remove(struct platform_device *pdev) { - misc_deregister(&imx2_wdt_miscdev); + struct watchdog_device *wdog = platform_get_drvdata(pdev); + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); - if (test_bit(IMX2_WDT_STATUS_STARTED, &imx2_wdt.status)) { - del_timer_sync(&imx2_wdt.timer); + watchdog_unregister_device(wdog); - dev_crit(imx2_wdt_miscdev.parent, - "Device removed: Expect reboot!\n"); + if (imx2_wdt_is_running(wdev)) { + del_timer_sync(&wdev->timer); + imx2_wdt_ping(wdog); + dev_crit(&pdev->dev, "Device removed: Expect reboot!\n"); } - - imx2_wdt_miscdev.parent = NULL; return 0; } static void imx2_wdt_shutdown(struct platform_device *pdev) { - if (test_bit(IMX2_WDT_STATUS_STARTED, &imx2_wdt.status)) { - /* we are running, we need to delete the timer but will give - * max timeout before reboot will take place */ - del_timer_sync(&imx2_wdt.timer); - imx2_wdt_set_timeout(IMX2_WDT_MAX_TIME); - imx2_wdt_ping(); - - dev_crit(imx2_wdt_miscdev.parent, - "Device shutdown: Expect reboot!\n"); + struct watchdog_device *wdog = platform_get_drvdata(pdev); + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); + + if (imx2_wdt_is_running(wdev)) { + /* + * We are running, we need to delete the timer but will + * give max timeout before reboot will take place + */ + del_timer_sync(&wdev->timer); + imx2_wdt_set_timeout(wdog, IMX2_WDT_MAX_TIME); + imx2_wdt_ping(wdog); + dev_crit(&pdev->dev, "Device shutdown: Expect reboot!\n"); } } -- 2.34.1